RT Generic T1 Eosinophil cationic protein is not only a distinctive eosinophil protein A1 Monteseirín, J A1 Vega, A K1 eosinophils K1 neutrófilos K1 eusinófilos AB We read with interest the article by Qiu et al (Thorax 2007;62:475–82). In this paper, neutrophils and eosinophils were identified using mouse anti-human neutrophil elastase and anti-eosinophil cationic protein (ECP), both monoclonal antibodies (mAbs). mAbs against ECP have been used to detect total eosinophils, but immunostaining techniques evidenced that the number of ECP+ cells was higher than the number of eosinophils.1 Recent studies show that ECP is not only a distinctive eosinophil protein, but has been found in neutrophils.1–3 PB British Thoracic Society (BTS) SN 0040-6376 YR 2008 FD 2008-02 LK http://hdl.handle.net/10668/368 UL http://hdl.handle.net/10668/368 LA en NO Monteseirín J, Vega A. Eosinophil cationic protein is not only a distinctive eosinophil protein. Thorax. 2008 Feb;63(2):185; authors' reply 185. DS RISalud RD Apr 5, 2025